The present invention relates to content distribution over a network, and more particularly, to managing distribution resources for video-on-demand (VOD) and other content services on a cable network.
Video-on-demand, one of several services offered by cable multiple system operators (MSOs), enables a subscriber to customize cable content according to their preferences and/or schedules. A typical VOD distribution architecture 10, shown in FIG. 1, includes a VOD server 12 and a session manager 14, a number of edge quadrature amplitude modulation (QAM) interfacing devices 16, a cable access network 18, and a set top box (STB) 20.
The VOD server 12 hosts a large volume of digital video content. Portions of this content may be selected via a request from the subscriber. (i.e., the end user). The session manager 14 is responsible for setting up a video session, i.e., processing requests from the subscriber and providing an interface between the VOD server 12 and the other components in the distribution architecture 10. The VOD server 12 and the session manager 13 are typically tightly coupled and sold as a set.
The edge QAM interfacing devices (edge QAM) 16 receive digital video content from the session manager 14, QAM-modulate and up-convert the content, then transmit resulting QAM signal onto the coaxial infrastructures within the access network 18.
The STB 20 terminates the QAM signals at the site of the subscriber and extracts the VOD content stream. The STB 20 then generates an output signal suitable for the subscriber's video equipment (e.g., televisions, recording devices, etc.).
In operation, the subscriber requests content (e.g., a movie, a nature documentary or a classic sporting event) via the STB 20. The STB 20 conveys the request to the session manager 14. The session manager 14 allocates suitable bandwidth resources in the edge QAM 16, and instructs the STB 20 to tune to the appropriate frequency spectrum for those resources. The session manager 14 then directs the VOD server 12 to begin streaming the appropriate digital content to the edge QAM 16, and the edge QAM 16 translates the digital content to the appropriate frequency spectrum.
One disadvantage of this architecture is that the edge QAM 16 is statically mapped to a particular session manager/VOD server combination, and cannot be shared with another session manager. The session manager 14 in FIG. 1 monitors and controls the resource allocation of the edge QAM 16 for VOD content to multiple subscribers. A second session manager/VOD server combination cannot share the edge QAM 16 because different session managers cannot communicate to coordinate the edge QAM resources.
For example, if a cable MSO desires to deploy a second VOD server 22 (and associated session manager 24) for hosting content different than what is on the first VOD server 12, the second VOD server 22 must deliver its content via different edge QAM 26 than that used by the first VOD server 12, as shown in FIG. 2. This arrangement represents a highly inefficient use of network resources.